Direct quote from the school handbook "If your child receives any injury during school hours, either an "acccident/incident report" will be written for you to sign. Parents will also be notified if any accident or incident occurs. Any head injuries are reason for immediate parent notification."
On school work "Age appropriate progress reports will be provided daily and a formal report (i.e. report card) will be sent home four times a year. These reports daily reports can be verbal or in written form and are part of our evaluation of the student's development."
I don't think I'm being unreasonable.
If that is the school's policy, I don't think so either in this case. I would email the teacher and just let her know you are concerned and because of the policy expected to be notified. If she gives you any problems then you can take it higher, but I would give her a chance to explain first.